According to her Wikipedia article, Catherine Kitty Stephens was a renowned opera singer and actress between 1813 and 1835. In 1838, she married George Capel-Coningsby, 5th Earl of Essex, an octogenarian widower, who died in 1839.
From Wikimedia.
Kitty Stephens is shown playing a string instrument while wearing an Empire waisted dress witha high, ruff-lined neckline and long upper puffed sleeves.
Keywords: Harlow, Catherine Stephens, Kitty Stephens, Countess of Essex, Capell family, British, curly coiffure, hat, high neckline, ruff, bodice, long close upper puffed sleeves, waist band, Empire waistline, close skirt